Answer: Coterminal Angles are angles who share the same initial side and terminal sides. Finding coterminal angles is as simple as adding or subtracting 360° or 2π to each angle, depending on whether the given angle is in degrees or radians.
It's a half of an equilateral triangle because their angles measure 30° and 60° (an equilateral triangle has 3 angles of 60°) So x=(2h/√3)/2=h√3=27√3≈15.6
